Background: Lower limb strength is crucial for stability and functional movement, such as walking, running, squatting, and balance, with the gluteus maximus (Gmax) being pivotal. Squat exercises are commonly used to strengthen the Gmax; however, the impact of ankle position on muscle activation during squats is not well understood. Objects: This study examined Gmax and lower limb muscle activation patterns in three ankle positions during squats, aiming to optimize rehabilitation strategies and enhance exercise prescriptions. Methods: Surface electromyography recorded the activation levels of the Gmax, vastus medialis oblique (VMO), vastus lateralis oblique (VLO), and biceps femoris (BF) across three ankle positions: neutral (NEU), dorsiflexion (DF), and plantarflexion (PF). A repeated-measures design was employed, involving 30 healthy adults (26 males and 4 females) aged 18–30 years. Muscle activation patterns were statistically analyzed to identify significant variations across these conditions, with the significance level set at p < 0.05. Results: During squats, DF of the ankle joint significantly increased Gmax activation compared with PF and NEU positions, indicating that an ankle position closer to DF may enhance hip extension. In contrast, PF was associated with heightened activation of the VMO and VLO, suggesting that this position may be beneficial for exercises focusing on knee stability. No significant changes were observed in the BF activation across the ankle positions, indicative of its limited involvement in response to variations in ankle positioning. Conclusion: These results underscore the importance of ankle joint positioning in modulating lower-limb muscle engagement during squatting. Ankle DF may be recommended to maximize Gmax activation, which is beneficial for hip-focused strengthening, whereas PF may supports knee stability by targeting quadriceps activation. This study provides evidence for adjusting ankle positioning during squat exercises to optimize specific rehabilitation and performance outcomes.

Background: The widespread use of smartphones and personal computers has contributed to a rise in thoracic kyphosis, a condition characterized by excessive outward curvature of the upper back. This condition can lead to reduced lung function, poor posture, and decreased spinal angles, all of which can cause reductions in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1). Furthermore, these issues are often associated with scapular protraction and anterior tilting. Objects: This study aimed to investigate the effects of using a scapular support pillow in people with thoracic kyphosis, as well as determine the changes in respiratory capacity and postural alignment. Methods: Forty-one participants (25 males and 16 females) with thoracic kyphosis (Cobb angle > 40°) were included in the study. Their respiratory function (FVC, FEV1) and body posture (spinal angle, chest expansion, acromion-to-the-wall index) were measured before and after using the scapular support pillow for approximately 30 minutes. FVC, FEV1, spinal angle, chest expansion, and acromion-to-the-wall index were analyzed using paired-t test. The level of statistical significance was set at p < 0.05. Results: The results demonstrated significant improvements in all measured parameters. Both respiratory function and posture-related metrics showed notable increases after using the scapular support pillow. Conclusion: The use of a scapular support pillow can effectively improve respiratory function and postural alignment in patients with thoracic kyphosis. Our research makes a meaningful contribution by proposing an effortless and convenient treatment option for individuals with thoracic kyphosis.

Background: For instance, forward head posture (FHP), characterized by the forward movement of the head relative to the spine, places significant stress on the neck and upper back muscles, disrupting the biomechanical balance of the body. Objects: The objective of this study was to probe the biomechanical effects of FHP on musculoskeletal health through a relative analysis of 26 adults diagnosed with FHP and 26 healthy controls. Methods: In this study, we evaluated the biomechanical impacts of FHP. Participants adjusted their head positions and underwent muscle strength tests, including electromyography assessments and the Biering-Sørensen test for trunk muscle endurance. Data analysis was conducted using Kinovea (Kinovea) and IBM SPSS software ver. 26.0 (IBM Co.) to compare muscle activities between groups with normal and FHPs. Results: The study shows that individuals with FHP have significantly lower muscle activity, endurance, and spinal extension in the erector spinae compared to those without, highlighting the detrimental effects of FHP on these muscles. Conclusion: This study underscores the impact of FHP on erector spinae function and emphasizes the need for posture correction to enhance musculoskeletal health and guide future research on intervention strategies.